
APRIL 22, 1915| 
NATURE 
207 

by a gas (so-called) radiator with window open | and the conditions for comfortable mental work 
at top a few inches, and three doors, beneath 








baa 
fic. 2.—Diagram of the Caleometer. I., 1I., IIT. and IV. are the arms of 
a Wheatsione Bridge. When the caleometer coil IV. becomes warmer 
than 40° C. the index of the galvanometer VI. (used as a relay) goes 
upwards in the diagram and completes the circuit which includes the 
upper half of the electro-magnetic coil VII., the soft iron plunger moves 
then upwards and increases the resistance in VIII., less current then 
passes and the coil IV. cools. When the caleometer coil IV. cools 
below 40° C. the index of the relay VI. moves downwards and com- 
pletes the circuit which includes the lower half of the coil VII. and 
this pulls down the slider and lessens the resistance in VIII. V indicates 
the watts or calories required to keep IV. at 4o° C. 
[ 
=F... 


Fic. 3.—The Caleometer. 
ling slider. 
moves in oil-bath, A string passes from the plunger over a pulley 
wheel on the slider to a counter-balancing weight and actuates the 
slider, E, the galvanometer acting as relay. 
A, caleometer coil. 
D, magnetic coils surrounding soft iron plunger which 
B, watt meter. C, travel- 
which the draught entered, the feet felt very cold 
and the head felt stuffy, the nose was congested, 
NO.. 2373, VOL. 95] 

at a desk were bad. The katathermometer 
showed that the rate of cooling at foot level was 
40 per cent. greater than at head level. On 
heating the same room by a_ properly flued 
gas fire, and securing warm feet by exposing 
them to its radiant heat, comfort was at once 
secured. The katathermometer showed that the 
rate of cooling at the level where the feet were 
was 30 per cent, slower than at head level.! 
The caleometer, by its automatic action, indi- 
cates the amount of heat energy required to keep 
a small coil of wire at body temperature. The 
oscillations of the indicator show the cooling: effect 
of moving air and the variations of air currents. 
If the atmosphere is still and monotonous, the 
oscillations of the indicator will be small and few 
in number. 
Records of any number (up to eight) of caleo- 
meter coils, placed in different parts of, say, a 
factory, can be taken by using a self-recording 
watt-meter.2 The instrument is seen in Pig. 3. 
LrEonaRD Hitt. 
AIDS TO NATURE-STUDY.? 
(1) it pees entomologist’s walls in life is in many 
respects an enviable one, for it is his 
particular business to study creatures which often 
exhibit great beauty, amazing variety, and a 
strange subtlety of behaviour. The current of 
research as regards molluscs or mammals, let us 
say, has a strong, quiet flow, but that in entomo- 
logy recalls a mountain stream with novelties 
and surprises at every turn. We feel this more 
than ever as we read Mr. Step’s fascinating 
“Marvels of Insect Life.’’ With*the aid of beau- 
tiful photographs, many of them from his own 
camera, he gives us a lively sense of the wonder- 
ful intricacy of insect-behaviour, which often 
seems like a caricature of that of higher animals. 
But no one knows what its most accurate psycho- 
logical interpretation may be. 
The author writes with clearness and accuracy, 
and there is no fussiness in his enthusiasm. He 
is to be congratulated on having secured Mr. 
Theo. Carreras as a draughtsman, for the full- 
page plates are exceptionally clever, and most of 
those in colour are as successful as they are 
daring. In its whole get-up the book is certainly 
at high-water mark. Two minor features may 
be mentioned which show that there has been 
careful consideration of what an intelligent reader 
reasonably expects and rarely gets. One is that 
the technical names of the insects dealt with are 
1 Volunteers who will undertake daily readings with the katathermometer 
are asked to communicate with the writer (London Hosptal Med cal 
College, E.). He is seeking to secure during the next six months records of 
open-air conditions in representative parts of Britain, and of those conditions 
which obtain in houses, schools, and factories. 
2 The instrument is made by Mr, Robert W. Paul, Newton Avenue 
Works, New Southgate, London, N. 
3 (1) ‘Marvels of Insect Life. A Popular Account of Structure and 
Habit.” Edited by FE. Step. Pp. viii+486. (London: Hutchinson and 
Co., n.d.) Price tos. 67. ne’. i 
(2) “Natur Notes for Ocean Voyagers.” By Capt. A. Carpenter and 
Capt. D. Wilson-Barker, Pp. xvit+181, (London: C, Griffinand Co., Ltd., 
1915.) Price 5s. net. aes 
(3) ‘‘ The Drama of the Year.”' By Mary Ritchie. Pp, x+118. (London: 
T. C. and E. C. Jack, 1915.) Price 2s. 
, 
